Principle Capacitance Level Indicator: Utilizes the capacitance formed between the sensing probe and the metallic vessel wall. A high frequency sine-wave is applied between the probe and the vessel wall.
A change of the medium level will induce a change in the current of the applied sine wave.
From Z=1/2pfc, when the capacitance in the vessel increase, impedance will decrease and current will increase. Vice-versa, when the capacitance in the vessel is small, the impedance will increase and current will decrease accordingly. Features Suitable for high temperature, high pressure and corrosive environment. Not affected by noisy, dusty, misty and changes in the temperature. No blind distance, ideal for different tanks. Economic for large tanks 4~20mA output compatible for most control systems and meters
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